Feeding device



April 26, 1932. w. P. VAN EPS FEEDING DEVICE Filed March 26, 1930 INVENTOR a k L git IFi'Hia 1-?I a H15 ATTORNEY Patented Apr. 26, 1 932 UNITED STATES PATENT OFFICE WILLIAM I. VAN EPS, OF PLAINFIELD, NEW JERSEY; ASSIGNOR TO ING-ERSOLL-RAND COMPANY, OF JERSEY GITY, NEW JERSEY, A CORPORATION OF NEW JERSEY FEEDING DEVICE Application filed larch 26, 1930. Serial No. 438,992.

This invention relates to rock drills, but more particularly to a feeding device for fluid actuated rock drills of the drifter type.

The objects of the invention are to maintain a suitable pressure on the drilling apparatus for feeding it towards the work in accordance with the penetration of the drill steel into the material being drilled and to facilitate the operation of withdrawing the drilling apparatus from the work.

Other objects will be in part obvious and in part pointed out hereinafter.

In the accompanying drawings illustrating the invention and in which similar reference characters refer to similar parts,

Fi ure 1 is a longitudinal sectional view of the feeding device showing it applied to a drifter and its support,

Figure 2 is an end view of the feeding device partly broken away, and

Figure 3 is a top plan view illustrating the manner in which the feeding device is supported.

Referring to the drawings, A designates generally a rock drill of which only the back head B and a portion of the cylinder C are shown to illustrate the application of the invention. The rock drill illustrated may be of the drifter type in which the cylinder C is provided with the usual ribs D extending longitudinally thereof on opposite sides and which ribs are adapted to slide in guideways E of a support for the drill, such as a shell The shell F may be of any well known type adapted to be clamped to a column or bar (not shown) to form a guide for the rock'drill A.

In accordance with the present invention, means are provided for actuating the rock drill A longitudinally of the shell F both in the direction of the work and to retract the drill A from the work. The means provided forthis purpose consists of a feeding device designated generally by G and comprising outer and inner tubular members H and J "respectively which are telescopically arranged with respect to each other so that.

the inner member J is capable of movement in allpngitudinal direction in the outer mem her r The outer member, in this instance, is suitably supported by standards K in the form of bolts L which are secured to the rear end of the shell F at one end and with the other for holding these elements in suitably spaced relation with'respect to each other.

The inner member J is provided with a piston head P having an end pressure surface Q against which pressure fluid in the rear end of the outer member H acts for actuating the inner member J forwardly in the direction of the shell F. On the front end of the head P is a pressure surface R of smaller area than the pressure surface Q, and against which pressure fluid in the front end of the outer member H acts for actuating the inner member J rearwardly.

The interior of the inner member J is in the form of a piston chamber S to accommodate a piston T which is adapted to reciprocate within the piston chamber S and is connected to the rear end of a piston rod U, the opposite or front end of the rod being connected to a lug V which may be located on the cylinder C.

The front end of the inner member through which the piston rod U reciprocates is provided with a suitable closure in the form of a head W having a bore X therein for the accommodation of the rod U. Preferably suitable sealing'material, such as a cup leather Y, is disposed in the bore X to form a seal around the rod U, and a gland Z may be threaded into the bore X to secure the cup leather Y in position.

Located on the outer member H is a valve chest 6 having a valve chamber 0 wherein is disposed a throttle valve cl of the rotary type having a suitable lever 6 whereby said throttle valve may be manipulated. Within the throttle vale d is a recess f which is constantly supplied with pressure fluid conveyed thereto by a coupling or connection 9 which is attached to the valve chest 6.

Leading from the valve chamber a to th rear end of the outer member His a supply passage it through which pressure fluid may be introduced into the member H for actuating the member J forwardly in the direction of the shell F. In the throttle valve (Z is a port j which is adapted to register with the passage It and also with a passage k leading to a bore 0 which extends longitudinally of the outer member H and on one side thereof. The bore 0 serves both as a pressure supp y pas ge g and als as a g i e for a tube 12 which is; adapted to slide Within the bore 0 and is secured with its front end to the head W. The passage g in thetube p registers at its front end with a passage 9" in the head W for introducingpressure fluid into the front end of the inner member J.

Pressure fluid intended to act against the pressure surface R for actuating the inner member J rearwardly is conveyed to the front end of the outer member by a supply passage 8 which extends from the valve chamber 0 through the outer member H and opens into the front end of the said outer member. In order to insure constant pressure Within the front end of the outer memberH thethrottle valve (Z is provided with a port, t, which opens into a groove a in the periphery of the throttle valve d and which maybe of such extent that it will be inregistry with the supply passage 8, in the various positions Which the throttle valve d may assumo inpractice.

In the periphery of the throttle valve 03 and. in, the same transverse plane as, the port jiisapartl annular groove 1; which is adapted to esta lish communication between the passages. 7r. hi and an exhaust port, w in the valve chest 6 and leading to the. at Inosphere.

Inthe rear end or wallw of the inner memher-J are, formed passages y for admitting pressure fluid into the rear end of the piston chamber S directly from the rear end of the member H.

The operation of the device is as follows: Let it be assumed. that it. is intended. to. actuate the rock drill A in a. forwardly direction. If then. the throttle valve d be rotated to the position illustratedin Figure 1, pressure fluid will flow through the port j and the passage, 71 into thez rear end of the outer member II.. Such pressure fluid will then act against the pressure surface Q to move theinner member J forwardly. At the- Same time pressure fluidwill flow through-the passages 3 into the rear end of-the piston chamber S and will act against the pistonT.

As the drillingapparatusproceeds for- Wardly the innermember J and the piston T willbe moved in that direction. in unison until the head-P reaches: the front end of the outer member From then on only thepressure fluid acting against the piston T will be effective to drive the drilling apparatus forwardly; 1 5

ing apparatus is assisted to a considerable extent by gravity. The relative areas of the pressure surfaces- Q, and R are such, however,

that a suitable. )ressure for feedingthe drilling apparatus orwardl'y will at all times be assured.

After the drill steel has penetrated-the Work to the desiredextentor, in. other words, when the drilling apparatus has reached the foremost limit of its travel in the shell F the throttlevalvecl. may berotated to-carr the port y" into registry with the passage 6. In this position of the throttle valve cl the groove v will establish communication between the passage ii and the exhaust port w so that the pressure fluid in the rear ends of the outer member Hand the piston chamber S will be exhausted to the atmosphere. The pressure fluid then admitted into the front end of the piston chamber Sand that. acting against the pressure surface R will act to retract the iimermember. J and the piston T, and therefore the rock. drill A relatively to the shell F.

When the drilling apparatus.- has been retracted in the manner described the throttle valved may be rotatedto a position: in. which the groove 0 will establish communication between the passage is and theexhaust port w. The pressure fluid may then be exhausted from the front end of tlrePiston chamber '3 or may be. retained: therein as' in. the front end of the outer member to: holdthe rock drill A in the retracted position duringthe operation of changing drill steels.

Iclaim:

1. In a feedingidevic the combination of a-support and a motorslidable on the sup port, a feeding cylinder comprising inner and outer tubular members arranged telescopicah ly with respect to each, other, means for securing the outer member fixedly to. the. sup, port, a head on the inner member forming differential pressure surfaces, a piston in the inner member, a rod connecting the piston to the motor, front and rear supply passages the outer member for. introducing pressure. field into the ends of the outer member to actuate the inner member, saidfrontsupply passage being adapted-to constantly supplypressure fluid into thev outer member to, act against the pressure surface of, smaller area, a port in the rear end of the inner member:

to admit pressure fluid thereinto for actuating the piston forwardly, a pair of telescopically arranged tubes forming passages for introducing pressure fluid into the front end of the inner member to act against the piston for retracting the piston and the motor, and a throttle valve for controlling the passages.

2. In a feeding device, the combination of a support and a motor slidable on the support, a feeding cylinder comprising inner and outer tubular members arranged telescopically with respect to each other, means for securing the outer member fixedly to the support, a head on the inner member forming differential pressure surfaces,-a piston in the inner member, a rod connecting the piston to the motor, front and rear supply passages in the outer member for introducing pressure fluid into the ends of the outer member to actuate the inner member, said front supply passage being adapted to constantly supply pressure fluid into the outer member to act against the pressure surface of smaller area, a port in the rear end of the inner member to admit pressure fluid thereinto for actuating the piston forwardly, a pair of telescopically arranged tubes exteriorly of the members forming passages for introducing pressure fluid into the front end of the inner member to act against the piston for retracting the piston and the motor, and a throttle valve on the outer member for controlling the passages.

In testimony whereof I have signed this specification.

WILLIAM P. VAN EPS. 

